src/de/steamwar/misslewars/MWTeam.java

@@ -31,10 +31,7 @@ import org.bukkit.inventory.meta.ItemMeta;
 import org.bukkit.scoreboard.Objective;
 import org.bukkit.scoreboard.Team;
 
-import java.util.HashSet;
-import java.util.LinkedList;
-import java.util.Objects;
-import java.util.Set;
+import java.util.*;
 
 public class MWTeam {
     private static final ItemStack bow = new ItemStack(Material.BOW);
@@ -162,8 +159,11 @@ public class MWTeam {
     }
 
     public void reset() {
-        players.clear();
         openInvitations.clear();
+
+        List<Player> tempPlayer = new ArrayList<>(players);
+        players.clear();
+        tempPlayer.forEach(this::join);
     }
 
     public void invitePlayer(Player p) {

src/de/steamwar/misslewars/countdowns/EndCountdown.java

@@ -42,7 +42,6 @@ public class EndCountdown extends StateDependent {
     private void restart() {
         FightWorld.resetWorld();
         MissileWars.waiting();
-        Bukkit.getOnlinePlayers().forEach(JoinListener::join);
     }
 
     @Override